Patents by Inventor Tomoji Kumano

Tomoji Kumano has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5840131
    Abstract: A process for producing a grain-oriented electrical steel sheet excellent in the glass film and the magnetic properties by coating a steel sheet with an annealing separator, finish annealing the steel sheet, and baking an insulating coating agent, which comprises coating the steel sheet having been decarburization annealed with an annealing separator prepared by allowing 100 parts by weight of MgO to contain, in the course from the step of producing MgO to the stage of preparing a slurry in the step of coating the steel sheet with MgO, halogens selected from F, Cl, Br and I or compounds of the halogens in an amount of 0.015 to 0.120 part by weight in terms of F, Cl, Br and I, and finish annealing the steel sheet.
    Type: Grant
    Filed: May 17, 1997
    Date of Patent: November 24, 1998
    Assignee: Nippon Steel Corporation
    Inventors: Kenichi Yakashiro, Hotaka Honma, Maremizu Ishibashi, Akira Sakaida, Tomoji Kumano, Koji Yamasaki, Katsuro Kuroki, Osamu Tanaka
  • Patent number: 5803989
    Abstract: A process for producing a non-oriented electrical steel sheet, comprising the steps of: hot rolling a non-oriented electrical steel sheet of a steel comprising at least one element selected from the group consisting of Si, Mn, and Al in respective amounts, in terms of by weight, satisfying the requirements 0.10%.ltoreq.Si.ltoreq.2.50%, 0.10%.ltoreq.Al.ltoreq.1.00%, 0.10%.ltoreq.Mn.ltoreq.2.00%, and the total amount of Si and Al being (Si+2Al).ltoreq.2.50%, with the balance consisting of Fe and unavoidable impurities, to prepare a hot rolled sheet; either subjecting the hot rolled sheet to single pass rolling to a final sheet thickness followed by finish annealing, or cold rolling the hot rolled sheet and then finish annealing the cold rolled sheet followed by skin pass rolling with a reduction ratio of 2 to 20% to a final sheet thickness, wherein the finishing in the step of finish hot rolling is performed in a temperature region of (Ar.sub.3 +50).degree. C.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: September 8, 1998
    Assignee: Nippon Steel Corporation
    Inventors: Ryutaro Kawamata, Takeshi Kubota, Tomoji Kumano
  • Patent number: 5685920
    Abstract: Disclosed is an annealing separator for production for grain-oriented electrical steel sheet, containing one or more compound selected from the following general formula;?Mg.sub.1-x M.sup.3+.sub.x !O ?Mg.sub.1-x M.sup.2+.sub.x !O or ?Mg.sub.1-x M.sup.2+.sub.x1 M.sup.3+.sub.x2 !OwhereM.sup.2+ is at least one bivalent element selected from the group consisting of Be, Ca, Ba, Sr, Sn, Mn, Fe, Co, Ni, Cu, Zn;M.sup.3+ is at least one tervalent element selected from the group consisting of Al, Fe, Cr, Co, B, Ti, Sb;0.01.ltoreq.x.ltoreq.0.40; x=x1+x2This annealing separator having a lower melting point and higher degree of reactivity is applied on the decarburization annealed strip, and improves the properties of the glass film, especially uniform film appearance and good sealing effect, and magnetic properties.
    Type: Grant
    Filed: May 12, 1995
    Date of Patent: November 11, 1997
    Assignee: Nippon Steel Corporation
    Inventors: Osamu Tanaka, Maremizu Ishibashi, Tsuyoshi Hamaya, Tsutomu Haratani, Tomoji Kumano, Koji Yamasaki, Akira Sakaida, Chihiro Sakurai, Hotaka Honma
  • Patent number: 5421912
    Abstract: A method of producing non-oriented electrical steel sheet comprising the steps of preparing steel comprising, by weight, up to 2.5% silicon, up to 1.0% aluminum and up to 2.5% (Si+2Al), with the remainder being iron and unavoidable impurities, hot rolling and cold rolling the steel to a final thickness and following this by finish annealing, wherein the average cooling rate between Ar.sub.3 and Ar.sub.1 during cooling transformation (.gamma..fwdarw..alpha.) of the steel is controlled to be 50.degree. C./s or less.
    Type: Grant
    Filed: March 15, 1994
    Date of Patent: June 6, 1995
    Assignee: Nippon Steel Corporation
    Inventors: Tomoji Kumano, Takeshi Kubota, Tadashi Nakayama, Hiroaki Masui, Yuji Yoshimura
  • Patent number: 4543134
    Abstract: The present invention provides an annealing separator comprising from 0.05 to 2.0 parts by weight of antimony sulfate based on 100 parts by weight of magnesium oxide, and at least one chloride selected from the group consisting of Sb, Sr, Ti, and Zr chlorides in a chlorine amount of from 5 to 20% by weight based on 100% of the chloride and antimony sulfate, and occasionally comprises Ti oxide in an amount of from 0.5 to 10 parts.The annealing separator is applied on the decarburization annealed strip, and improves both the magnetic properties and properties of glass film, in the production of a grain-oriented electrical steel sheet.
    Type: Grant
    Filed: November 2, 1984
    Date of Patent: September 24, 1985
    Assignee: Nippon Steel Corporation
    Inventors: Osamu Tanaka, Shozaburo Nakashima, Takashi Nagano, Tomoji Kumano, Yoshitaka Hiromae